Adding "adapter" ORTC objects on top of ChannelManager/BaseChannel/etc.

webrtc/ortc/rtpreceivershim.h

+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_ORTC_RTPRECEIVERSHIM_H_
+#define WEBRTC_ORTC_RTPRECEIVERSHIM_H_
+
+#include <memory>
+
+#include "webrtc/api/ortc/ortcrtpreceiverinterface.h"
+#include "webrtc/api/rtcerror.h"
+#include "webrtc/api/rtpparameters.h"
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/base/thread.h"
+#include "webrtc/ortc/rtptransportcontrollershim.h"
+#include "webrtc/ortc/rtptransportshim.h"
+#include "webrtc/pc/rtpreceiver.h"
+
+namespace webrtc {
+
+// Implementation of OrtcRtpReceiverInterface that works with RtpTransportShim,
+// and wraps a VideoRtpReceiver/AudioRtpReceiver that's normally used with the
+// PeerConnection.
+//
+// TODO(deadbeef): When BaseChannel is split apart into separate
+// "RtpReceiver"/"RtpTransceiver"/"RtpReceiver"/"RtpReceiver" objects, this shim
+// object can be removed.
+class RtpReceiverShim : public OrtcRtpReceiverInterface {
+ public:
+  // Doesn't take ownership of |transport| or |rtp_transport_controller|.
+  //
+  // "Create" method is used (as opposed to just a constructor) because
+  // applying the parameters may fail.
+  //
+  // |worker_thread| can't be null, and is needed for the video track
+  // implementation.
+  static RTCErrorOr<std::unique_ptr<OrtcRtpReceiverInterface>> CreateProxied(
+      cricket::MediaType kind,
+      RtpTransportShim* transport);
+  ~RtpReceiverShim() override;
+
+  // OrtcRtpReceiverInterface implementation.
+  rtc::scoped_refptr<MediaStreamTrackInterface> GetTrack() const override;
+
+  RTCError SetTransport(RtpTransportInterface* transport) override;
+  RtpTransportInterface* GetTransport() const override;
+
+  RTCError Receive(const RtpParameters& parameters) override;
+  RtpParameters GetParameters() const override;
+
+  cricket::MediaType GetKind() const override;
+
+ private:
+  // Methods called internally be Create factory method.
+  RtpReceiverShim(cricket::MediaType kind,
+                  RtpTransportShim* transport,
+                  RtpTransportControllerShim* rtp_transport_controller);
+  void MaybeRecreateInternalReceiver();
+
+  cricket::MediaType kind_;
+  RtpTransportShim* transport_;
+  RtpTransportControllerShim* rtp_transport_controller_;
+  // Scoped refptr due to ref-counted interface, but we should be the only
+  // reference holder.
+  rtc::scoped_refptr<RtpReceiverInternal> internal_receiver_;
+  RtpParameters last_applied_parameters_;
+
+  RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(RtpReceiverShim);
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_ORTC_RTPRECEIVERSHIM_H_